Valve.



G. H. GILMAN.

VALVE.

APPLICATION FILED JUNI: zo, 1911.

Patented June 25, 1912.

coLuMlnA v1.11

UNITED STATES PATENT OFFICE.

GEORGE H. GILMAN, OF CLAREMONT, NEW HAMPSHIRE, ASSIGNOR TO SULLIVAN MACHINERY COMPANY, 0F CLAREMONT, NEW HAMPSHIRE, A CORPORATION OF MAINE.

VALVE.

Patented June 25, 1912.

Original application led January 3, 1911, Serial No. 600,403. Divided and this application led June 20,

To all whom it may concern:

Be it known that I, GEORGE I-I. GILMAN, a citizen of the United States, and a resident of Claremont, county of Sullivan, State of New Hampshire, (whose post-offce address is Claremont, New Hampshire,) have invented an Improvement in Valves, of which the following description, in connection with the accompanying drawings, is a specication, like characters on the drawings representing like parts.

This invention relates yto engines and more particularly though not exclusively to engines of the direct-acting type such as are used in connection with rock drills and other stone working machines, being more particularly concerned with improvements in the controlling valves of such engines.

This application is a division of my prior` co-pending application Serial No. 600,403, filed Jan. 3, 1911.

My invention will be best understood by reference to the following description when taken in connection with the accompanying illustration of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawings: Figure 1 is a plan view of a valve chamber casing showing the buffer springs; Fig. 2 is a sectional elevation taken through the valvechamber on the line 2 2 in Fig. 1; and Eig. 3 is a transverse sectional elevation taken through the valve chamber on the line 3 3 in Fig. 1.

Referring to the drawings, I have there shown for the purpose of illustrating the vinvention the valve chamber casing 1 of a rock drill. The other features of the drill are not directly concerned in the present invention and are omitted in order to make the showing of the present invention clearer.

Referring more particularly to the controlling valve 2 the latter is of the pressure' actuated piston type having a central head or spool 3 which alternately connects the supply chamber 4 with the ports 5 and 6,

the former leading to the rear or head endof the cylinder (not shown) and the latter to the forward or tool end of the cylinder. In the position of the valve shown the pressure passes from the supply chamber 4 through the port 5 to the head end of the cylinder, acting to drive the piston forward,

Serial No. 634,283.

the port 6 at the same time being connected about the contracted or stem portion of the valve with one end of the exhaust space 7. Then the valve is reversed the port 6 is connected with the supply chamber 4 and the head end port 5 with the opposite end of the exhaust space 7. To reverse the valve, the latter is provided at opposite ends with spools 8 and 9 which work in end chambers to which pressure is alternately admitted by the movement of the piston to throw the valve. The chamber containing the head 8 is connected by a passage 10 (see dotted lines) to an appropriate part of the cylinder and the chamber containing the head 9 is connected by means of the passage 11 with `an appropriate part of the cylinder, so that` such passages are alternately opened by the reciprocatory movement of the piston to admit pressure fluid to that end of the valve chamber with which the uncovered passage is connected, and exhausted from the opposite end, such admission of pressure iiuid reversing the position of the valve. Such type of valve is well known and requires no further description, it being herein disclosed and referred to merely as a type of any pressure actuated valve, the particular form and construction of such valve being immaterial for the purposes of the present invention.

In drills of this type the continued action of the pressure actuated valve upon its buffers, against which it is thrown with considerable force, tends to strip the threads of such buffers and the latter require to be frequently renewed. In the herein described form of engine I have provided threadless buffers which are adapted to yield slightly under the impact of the valve, the shock of the latter being taken by resilient means such as a spring against which the buffer rests.

Referring to the drawings, it will be seen that the movement of the valve is checked against the buifers 12 and 13 which are in the form of piston-shaped plugs having a sliding tit one in each end of the valve chamber, the buffers bearing respectively against the leaf springs 14 and 15. These springs are perforated at each end and through the perforations pass the tie rods or bolts 16 and 17, the latter having threaded ends engaging the nuts 18 which may be tightened to draw the springs closer together and increase the tension on the buffers. Each rod passes through the sleevelike walls 19 (see Fig. 3) of the valve chamber casing so thatI while passing from one end of the valve'chamber to the other it does not enter the pressure supply space thereof and does not therefore require to be packed. Then the valve is thrown and strikes a buffer, the shock upon the buffer is received by the springs and transmitted thereby through the rods 16 and 17 to the opposite spring so that the blow is sustained by both springs together. Each buffer seats against a shoulder in the end of the valve chamber and acts as an end closure for the chamber. It will be seen, however, that the tendency to move the buffer out and unseat it, which follows the striking of the end of the valve against the buiier, only occurs when the adv jacent end of the valve chamber is freed from pressure fluid. On the other hand, thc opposite end of the valve chamber, which at that moment is opened to t-he pressure iluid for the purpose of throwing the valve and maintaining it thrown, is more effectually closed against leakage at the buffer seat by the outward movement of the opposite buffer under the shock or impact of the valve which, acting through the springs and connecting reds, tends to draw the remaining buffer at the pressure filled end of the valve chamber more tightly to its seat. The result is that each end-seated buffer being automatically seated at the critical time by the impact upon the other buifer, can be given a comparatively loose sliding fit in the valve chamber, the end fit of the buffer being all that is required to keep the chamber pressure tight.

Vhile I have herein shown and described for purposes 0f illustration one specific form of the invent-ion, it is to be understood that the same is notlimited to the details of construction or relative arrangement of parts, but that extensive deviations may be made therefrom without departing from the spirit thereof.

Claims:

1. In an engine the combination with a pressure-actuated valve of buffer members for the opposite ends of said valve and a rigid movable connecting member for said buffer members passing from end to end but outside of said valve.

2. In an engine the combination with a pressure-actuated valve of movable buifers for the opposite ends of said valve, resilient means to receive the shock of said buifer members and a rigid movable connection between the opposite resilient means.

3. In an engine the combination with a pressure-actuated valve of movable buers for the opposite ends of said valve, springs against which said buffer members rest, abutting members for said springs, and a connecting rod for the springs of opposed .butter members.

4:. In an engine the combination with a pressure-actuated valve of movable buer members for the opposite ends of said valve,

a spring for each buffer member, an abutting member for each end of each spring, and a pair of rods connecting together the corresponding end of opposite springs.

5. In an engine having a valve chamber, the combination with a pressure-actuated valve, of movable buffer members seated in the opposite ends of the valve chamber, and

Vmeans including resilient connections connecting said buffer members tc cause the outward movement of one to more firmly seat the other.

6. In an engine having a valve chamber, the combination with a pressure-actuated valve, of movable buffer members seated in the opposite ends of the valve chamber, and means connecting said buer members to cause the outward movement of one to more firmly seat the other.

7. In an engine having a valve chamber, the combination with .a pressure-actuated valve of slidable buffer plugs seated in op posite ends of the valve chamber, a rod connecting opposite plugs and resilient means also interposed between the same to permit yielding movement of the plugs.

8. In an engine having a valve chamber, the combination with a pressure-actuated valve of slidable buffer plugs seated in opposite ends of the valve chamber, and a resilient connecting means between opposite plugs to permit yielding movement of one plug to cause the remaining one to be seated more firmly in the valve chamber.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses. y

GEORGE II. GILMAN.

Vitnesses:

CHAS. J. JONES, E. J. BOUCHARD.

Copies of this patent may be obtained for five` cents each, by addressing` theV v Commissioner of Patents,

Washington, D. C. 

